1. Field of the Invention
This invention relates, generally, to a safety-type cap and, more particularly, to a safety cap which is readily removable from a can or other similar enclosure without the use of undue force.
2. Discussion of the Prior Art
Ever since product safety awareness has become an important factor in packaging, numerous attempts have been made to prevent the unintended opening of containers, such as spray cans, screw tops and the like. This perennial solution was made more acute with various legislation mandating "child-proof" caps on various containers. Marketing considerations also required companies to produce a product package according to the demands of the consumer.
Accordingly, a number of child-proof or tamper-proof caps have been produced in this vein. One such example may be found in U.S. Pat. No. 3,037,672 "Dispenser Container with Tamper-Proof Replaceable Cap", issued June 5, 1962 to Gach. Gach requires the breaking of an integral portion of the cap before initial use, the cap thereafter serving as a conventional cap. Therefore, while this type of cap is sufficient to initially protect or prevent child tampering, it fails to provide the same level of protection on a continuing basis.
U.S. Pat. No. 3,690,519 "Closures for Containers", issued Sept. 12, 1972 to Wassilieff, is similar to the Gach patent in that an intermediate element is utilized which must be broken away before removal of the cap is permitted and therefore suffers from the same defect as the Gach reference.
U.S. Pat. No. 3,706,401 "Child-Proof Overcap for an Aerosol Can", issued Dec. 19, 1972 to Gach is more in line with the continuing child-proof protection and requires removal of the cap by pressing down upon the top thereof and simultaneously rotating it. While this does provide continued protection, it suffers from the disadvantage that substantial force is required in conjunction with turning in order to remove the cap. Therefore it is most inconvenient and difficult to use.
U.S. Pat. No. 3,820,683 "Spray Can Safety Cap", issued June 28, 1974 to Jasinski, suffers from much the same defects as the '401 reference in that squeezing or force, coupled with pulling, is required in order to remove the cap. An alternate embodiment allows for pushing of a component of the cap coupled with removal of the cap. However, these alternate designs and the basic concept still suffer from the defect. That is, substantial force is necessary in order to remove the cap.
Another type of child-proof container or cap may be found in U.S. Pat. No. 3,870,187 "Child-Proof Aerosol Cap", issued Mar. 11, 1975 to Bennett. This device facilitates removal of the cap by prying, such as through the use of a tool or the like. Another device which is conceptually similar to the Bennett reference is U.S. Pat. No. 3,854,622 "Childproof Cover", issued Dec. 17, 1974 to McKirnan and is indeed issued to the same assignee as the Bennett reference. This disclosure is somewhat similar to the previous patents in that squeezing of the cap coupled with pulling is required in order to remove the cap.
Another operatively similar device is disclosed in U.S. Pat. No. 3,934,751 "Safety Overcap for Dispensing Containers", issued Jan. 27, 1976 to Green et al. Green requires squeezing in order to releasably remove a portion of the container from the edge or lip of the container which must then be coupled with pulling of the cap away from the container.
U.S. Pat. No. 3,995,765 "Safety Closure for Containers", issued Dec. 7, 1976 to Burke improves slightly upon the previously mentioned squeeze and pull type of operation by providing a pair of opposed, longitudinally extending slots. U.S. Pat. No. 4,303,175 "Overcap Assembly for Valved Containers", issued Dec. 1, 1981 to Lux, requires exertion of pressure coupled with rotation thereof to remove the cap. U.S. Pat. No. 4,315,576 "Child Resistant Closure Cap Apparatus Employing Fulcrum Action", issued Feb. 16, 1982 to Murphy et al. requires sheer force in order to cause the cap to pivot about a fulcrum and release the cap from the container.
However, while all of the above-mentioned patents offer safety advantages over simple screw-type or pop-off type lids, they all suffer distinct disadvantages. Some of these disadvantages, in addition to those previously mentioned, are complex mechanical arrangements, critical wall thicknesses and the like. Additionally, one of the prime disadvantages is the requirement that substantial force be utilized in one fashion or another to remove the cap. Such force may take the form of squeezing, pulling, pushing or the like.
Furthermore, a significant number of these require coaction or two movements in order to remove the cap. That is, they require force in two (usually perpendicular) directions in order to remove the cap. Therefore, many require the use of squeezing and rotation or squeezing and pulling in order to remove the container. Therefore, while they satisfy the function of providing childproof safety caps, they are most difficult to utilize by the aged, disabled or crippled individual.
This is a particularly acute problem since it is well known that aged individuals simply do not have sufficient muscular strength in order to remove caps of this type. Further, they are often saddled with arthritis or other similar types of infirmities making such movements or the exertion of such force painful. Additionally, disabled individuals may simply not have the coordination to perform two functions, such as squeezing and pulling or squeezing and rotating.
Therefore, what is an advantage for younger, more capable individuals having children, is a distinct disadvantage for older or disabled individuals. This proposes a difficult problem for manufacturers which must then either lose sales to other products having perhaps less safe childproof caps to those which are more easily operable by the consumer. The extent of the "migration" will depend upon the individual's infirmity. Alternately, the manufacturer is forced to distribute their product having two different types of cap. It is well known that production of two different types of cap raises a number of problems, among them is the increased costs in separate distribution, manufacture and the like. Another problem is the danger of non-childproof containers winding up in households having children.
Accordingly, it is an object of the present invention to produce a device which is inexpensive to manufacture. It is a further object of the present invention to produce a device which is easy to assemble. Still a further object of the present invention is to produce a device which is easy to utilize.
A still further object of the present invention is to produce a device which does not require dual or contemporaneous motion, such as squeezing and lifting or the like. Yet another object of the present invention is to produce a device which is readily usable by the handicapped. A further object of the present invention is to produce a device which does not require significant force. Yet another object of the present invention is to produce a device which is capable of being used by aged and/or arthritic hands.
Still another object of the present invention is to produce a device which is childproof. Yet another object of the present invention is to produce a device which does not require that to be used on specially adapted containers or specially designed containers.
A further object of the present invention is to produce a device which may be repeatedly used during the life of the container. Still a further object of the present invention is to produce a device which does not require breaking away of a portion of the top or the like in order to initially remove the top. Yet another object of the present invention is to produce a device which does not require use of any tool, special or otherwise, in order to remove the top.
Yet another object of the present invention is to produce a device which is injection moldable and which may utilize low cost plastics suitable for high volume production.
Additionally, it is another object of the present invention to produce a locking removable cap for a container which has a lip thereon, having a first cap comprised of an annular ring, at least one vertically upstanding wall extending from the annular ring, at least two urgeable tabs coaxially extending downward from the annular wall, at least one retaining ledge disposed on each coaxial tab, which engages the lip of the container and thereby secures the cap to the container; and an overcap which is pivotable around the longitudinal axis of the first cap and which is comprised of an annular shell having a recess of reduced wall thickness which is rotatable into and out of alignment with at least one of the tabs, thereby respectively permitting and prohibiting radial outward movement of the corresponding tab and the retaining ledge out of engagement with the lip of the container for respectively permitting and prohibiting the removal of the locking removable cap from the container.